1. Field of the Invention
This invention relates to antennae, and more particularly to compressible spiral antennae, and is based upon Provisional Application Ser. No. 61/342,357, filed 13 Apr. 2010, and which is incorporated herein by reference in its entirety.
2. Prior Art Discussion
Helical antennas are known in the art for relatively simple construction and good gain characteristics, and for their circular polarization properties. Various loop and spiral antennas are made using cylindrical forms, or formed to maintain shape in free space using rigid materials. Collapsible antennas are known in the art. Generally, antennas that are deployed tend to be heavy, rigid and massive, owing to the design need to maintain accurate dimensions. In the antenna art, element sizes are often critical, diameters must be accurate, and the pitch of a helical antenna must have the correct spacing for optimal operation. For these reasons, rigid and or heavy materials are typically used for the conductors, or the conductors, which can be wire, flat wire, conductive tape etc. are supported by a rigid forms.
It would be desirable if less massive antennas of the helical variety could be produced that were lightweight, easily compressed into a flat shape, yet deployable at will, and instantly achieve and maintain necessary dimensions for proper operation. Many uses would be found for the successful adjustable, collapsible helical antenna in situations requiring fast set up and use, safety and or lack of damage to people and objects should the antenna fall from its mounting position, and if the antenna produced a circularly polarized response pattern over a relatively large bandwidth. Concerts, road show crews, audio-visual companies, and others who must quickly and safely set up lights, wireless microphones, stage equipment and the like would benefit, and their safety could be enhanced while affording better wireless coverage with less weight, mass and setup time.